Gmail has tightened security measures for making use of their outgoing mail server "smtp.gmail.com". When you setup Meteobridge to feed this server by using port 587 and using "starttls" protocol you might get the error message "Error: Failed to send email: msmtp: authentication failed (method PLAIN) msmtp: server message: 534-5.7.14"

This error indicates that Gmail finds given "starttls" encryption not being enough. As Gmail is aware that not all clients will be able to adapt to their stricter policies, they allow to drill down security measures for their smtp server to a reasonable level by selecting "Allow less secure apps to access accounts" in your Gmail settings.

When you send mails from different devices and locations via your Gmail account, Gmail will block sendings. Please visit this link to manually select the sending device as being one of yours: https://myaccount.google.com/security#activity